1 /* Locate the shared object symbol nearest a given address.
2 Copyright (C) 1996-2000, 2001, 2002 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
27 _dl_addr (const void *address
, Dl_info
*info
)
29 const ElfW(Addr
) addr
= DL_LOOKUP_ADDRESS (address
);
30 struct link_map
*l
, *match
;
31 const ElfW(Sym
) *symtab
, *matchsym
;
33 ElfW(Word
) strtabsize
;
35 /* Find the highest-addressed object that ADDRESS is not below. */
37 for (l
= GL(dl_loaded
); l
; l
= l
->l_next
)
38 if (addr
>= l
->l_map_start
&& addr
< l
->l_map_end
)
40 /* We know ADDRESS lies within L if in any shared object.
41 Make sure it isn't past the end of L's segments. */
42 size_t n
= l
->l_phnum
;
47 while (l
->l_phdr
[n
].p_type
!= PT_LOAD
);
48 if (addr
>= (l
->l_addr
+
49 l
->l_phdr
[n
].p_vaddr
+ l
->l_phdr
[n
].p_memsz
))
50 /* Off the end of the highest-addressed shared object. */
61 /* Now we know what object the address lies in. */
62 info
->dli_fname
= match
->l_name
;
63 info
->dli_fbase
= (void *) match
->l_addr
;
65 /* If this is the main program the information is incomplete. */
66 if (__builtin_expect (info
->dli_fbase
== NULL
, 0))
68 info
->dli_fname
= _dl_argv
[0];
69 info
->dli_fbase
= (void *) match
->l_map_start
;
72 symtab
= (const void *) D_PTR (match
, l_info
[DT_SYMTAB
]);
73 strtab
= (const void *) D_PTR (match
, l_info
[DT_STRTAB
]);
74 strtabsize
= match
->l_info
[DT_STRSZ
]->d_un
.d_val
;
76 /* We assume that the string table follows the symbol table, because
77 there is no way in ELF to know the size of the dynamic symbol table!! */
78 for (matchsym
= NULL
; (void *) symtab
< (void *) strtab
; ++symtab
)
79 if (addr
>= match
->l_addr
+ symtab
->st_value
80 && ((symtab
->st_size
== 0 && addr
== match
->l_addr
+ symtab
->st_value
)
81 || addr
< match
->l_addr
+ symtab
->st_value
+ symtab
->st_size
)
82 && symtab
->st_name
< strtabsize
83 && (matchsym
== NULL
|| matchsym
->st_value
< symtab
->st_value
)
84 && (ELFW(ST_BIND
) (symtab
->st_info
) == STB_GLOBAL
85 || ELFW(ST_BIND
) (symtab
->st_info
) == STB_WEAK
))
90 /* We found a symbol close by. Fill in its name and exact address. */
91 info
->dli_sname
= strtab
+ matchsym
->st_name
;
92 info
->dli_saddr
= (void *) (match
->l_addr
+ matchsym
->st_value
);
96 /* No symbol matches. We return only the containing object. */
97 info
->dli_sname
= NULL
;
98 info
->dli_saddr
= NULL
;